Gigabyte = if you want the get the performance its showing now and dont want to keep the card for long run.(3years warranty)
EVGA = this i don't how the Sc version & FTW perform compared to Gigabyte,but has good customer service.Quick response regarding RMA support and includes lifetime warranty for their products.

I think that EVGA changed their warranty, and that almost all their GFX cards have a 3 year warranty, but that it is now transferable. The only 670 cards that I am seeing them sell have the "-KR" code at the end, which means it is a 3 year limited warranty.

Go with the gigabyte, 95% chance it will be a better overclocker than the EVGA version, runs cooler and quieter too. I was a strict EVGA guy before this (260, 470, SLi 560's, 580) but I decided to go with the Gigabyte 670 and am very happy I did.Edited by g00s3y - 5/19/12 at 6:02am

I think that EVGA changed their warranty, and that almost all their GFX cards have a 3 year warranty, but that it is now transferable. The only 670 cards that I am seeing them sell have the "-KR" code at the end, which means it is a 3 year limited warranty.Source 1Source 2
Go with the gigabyte, 95% chance it will be a better overclocker than the EVGA version, runs cooler and quieter too. I was a strict EVGA guy before this (260, 470, SLi 560's, 580) but I decided to go with the Gigabyte 670 and am very happy I did.

But even so I haven't heard anything great about Gigabyte's support, but I have heard great things about EVGA's support and RMA. Plus EVGA guys are pretty active in the community from what I see. But I'm sure both brands are great. This was my first stint with powercolor for example and they are the only ones that made a single slot 7750. And the card has been great. But I haven't had any experience with their support/rma however.

I'm planning on going with the ASUS. I've bought ASUS for the last 2 cards I've had and have no regrets. Previously I've purchased EVGA cards almost exclusively. No problems with them I just like the DCII cooler better and so far I've been able to OC all the ASUS cards really well.